renewmessage.java

来自「High performance DB query」· Java 代码 · 共 154 行

/*
 * @(#)$Id: RenewMessage.java,v 1.8 2004/07/02 23:59:20 huebsch Exp $
 *
 * Copyright (c) 2001-2004 Regents of the University of California.
 * All rights reserved.
 *
 * This file is distributed under the terms in the attached BERKELEY-LICENSE
 * file. If you do not find these files, copies can be found by writing to:
 * Computer Science Division, Database Group, Universite of California,
 * 617 Soda Hall #1776, Berkeley, CA 94720-1776. Attention: Berkeley License
 *
 * Copyright (c) 2003-2004 Intel Corporation. All rights reserved.
 *
 * This file is distributed under the terms in the attached INTEL-LICENSE file.
 * If you do not find these files, copies can be found by writing to:
 * Intel Research Berkeley, 2150 Shattuck Avenue, Suite 1300,
 * Berkeley, CA, 94704.  Attention:  Intel License Inquiry.
 */


package overlay.provider.basic;

import services.network.Payload;
import util.BitID;
import util.FreeList;
import util.FreeListFactory;
import util.network.serialization.GenericByteBuffer;
import util.network.serialization.SerializationManager;

/**
 * Class RenewMessage
 *
 */
public class RenewMessage extends ProviderMessage {

    public static long serialVersionUID =
        SerializationManager.getSerialUID(
            "overlay.provider.basic.RenewMessage");

    // the instance ID of the item
    private int iid;

    // the item's lifetime
    private long lifetime;

    // free list of objects for better memory management
    private static FreeList freeList = new FreeList(new RenewMessageFactory());

    /**
     * DeSerialize the object from the provided GenericByteBuffer.
     *
     * @param inputBuffer
     */
    public RenewMessage(GenericByteBuffer inputBuffer) {
        super(inputBuffer);

        this.iid = inputBuffer.getInt();
        this.lifetime = inputBuffer.getLong();
        this.size += Payload.LONG_SIZE;
    }

    /**
     * Serialize the object into the provided GenericByteBuffer.
     *
     * @param outputBuffer
     * @return
     */
    public long serialize(GenericByteBuffer outputBuffer) {
        super.serialize(outputBuffer);
        outputBuffer.putInt(iid);
        outputBuffer.putLong(lifetime);

        return serialVersionUID;
    }

    /**
     * Constructor RenewMessage
     */
    protected RenewMessage() {}

    private void init(Integer messageID, String ns, String rid,
                      BitID locationID, int iid, long lifetime) {
        super.init(messageID, ns, rid, locationID);

        this.iid = iid;
        this.lifetime = lifetime;

        // set the size
        size += Payload.LONG_SIZE;
    }

    /**
     * Method getIID
     * @return
     */
    public int getIID() {
        return iid;
    }

    /**
     * Method getLifetime
     * @return
     */
    public long getLifetime() {
        return lifetime;
    }

    /**
     * Method allocate
     *
     * @param messageID
     * @param ns
     * @param rid
     * @param locationID
     * @param iid
     * @param lifetime
     * @return
     */
    public static RenewMessage allocate(Integer messageID, String ns,
                                        String rid, BitID locationID, int iid,
                                        long lifetime) {
        RenewMessage message = (RenewMessage) freeList.allocate();

        message.init(messageID, ns, rid, locationID, iid, lifetime);

        return message;
    }

    /**
     * Method free
     *
     * @param message
     */
    public static void free(RenewMessage message) {
        freeList.free(message);
    }
}


/**
 * Class RenewMessageFactory
 *
 */
class RenewMessageFactory implements FreeListFactory {

    /**
     * Method create
     * @return
     */
    public Object create() {
        return new RenewMessage();
    }
}